How to upgrade from 10.5.8 to 10.8
I just purchased the newest nano, however i was unaware that i needed to upgrade my itunes in order to do so. Now in order to upgrade to the right version of itunes i need to move from 10.5.8 to atleast 10.8. Could someone help me out? I'm not too familar with any of this and terms such as snow leopard and mountain lion mean close to nothing to me, if you know what I mean.
iMac, Mac OS X (10.5.8)